I personally think this song is about a person that is in love with someone, but they like someone else, rather then death (which I’ve seen other people talk about), and I will explain later why. Maybe like a best friend.
“I'm building this house, on the moon
Like a lost, astronaut”
He is settling on the moon, lingering around in space, probably meaning that he’s lost, but still holding on to something / a place
“Lookin' at you, like a star
From a place, the world forgot”
A star, which is far away, like the person is far away. But it’s from a place that nobody knows / forgotten, so he is either forgotten by that person or his support / love is taken for granted.
“And there's nothing, that I can do
Except bury my love for you”
And because that person doesn’t know how he feel, or rejected them, there is nothing that he can except bury his love for that person.
“The brightness of the sun, will give me just enough
To bury my love, in the Moondust”
This can mean that because of another person (because the sun is also a star), he has the willingness to let go, or that because moon reflects the sun, that it is bright enough to carefully let go (bury his love). Or both, but this depends on how you interpret it.
“Nothing can breath, in the space
Colder than, the darkest sea”
There is nothing that can breathe, so that could mean his love for that person “died”, or he is struggling to breathe themselves. But this again depends on how you interpret it.
“I have dreams about the days, Driving through your sunset breeze
But the first thing, that I will do
Is bury my love for you”
He remember the memories they had together, but after he remembers those things, he still lets go or buries his love.
“I long to hear your voice, but still I make the choice
To bury my love, in the moondust”
I feel this emphasizes on the fact that he still remembers them and still wants them but he still makes the choice to let go.
“I'm a cast away, and men reap what they sow
And I say what I know, to be true”
This is one of those cryptic parts, and I had to think about it for a moment. For me it maybe be that he wasn’t what they ‘sowed’ and thus didn’t fit in. It could also mean that when you sow, you practically bury things and that his love is growing, but this is a but weird, because nothing can breathe there. He only says things that he knows is true, but this can be a bit tricky, because everyone has a different perception of what is true or not. This can also be linked to the fact that he wasn’t what they ‘sowed.’
“Yeah I'm living far away, on the face of the moon
I've buried my love to give the world to you”
This is the part why I think it’s not about death. He’s living far away from the person, wants to meet them but still doesn’t. It would be unreasonable to say that the person he loves is dead, because he gave the world to the person by burying his love. Meaning that they either didn’t have a good relationship, or they already like someone else.
I personally think this song is about a person that is in love with someone, but they like someone else, rather then death (which I’ve seen other people talk about), and I will explain later why. Maybe like a best friend.